Secondary glaucomas often seriously threaten vision and may be very difficult to treat. Extensive research is needed for better understanding of the causes of these glaucomas and for development of better treatments. We propose to carry out clinical studies in correlation with laboratory investigations of disease mechanisms. concentrating on uveitis-induced glaucoma, exfoliation glaucoma, lens-induced glaucoma, neovascular glaucoma, pigmentary glaucoma, and glaucoma associated with abnormal pressure in episcleral vessels. We aim to accomplish clinico-pathologic correlations through a combination of special clinical studies and investigations of biopsy and necropsy materials, utilizing procedures that we have already developed and in operation as well as new procedures that are under development. We propose evaluating relevant therapeutic measures through controlled clinical trials. The Massachusetts Eye and Ear Infirmary Glaucoma Clinic and Research Laboratories are available. Also the Director of the Glaucoma Service (as Principal Investigator) and a corps of highly qualified, cooperative, clinical and laboratory investigators dedicated to work on Glaucoma are available. This group has suitable autonomy, and has enthusiastic encouragement by the related hospital and medical school administrations. Several investigators have support for laboratory glaucoma research. Cooperative out-patients are available in ample numbers, along with adequate control patients having no glaucoma, or having primary glaucoma for comparison.